Bilateral laryngeal paralysis is a serious and often life-threatening clinical condition. The recurrent laryngeal nerve (RLN) carries motor fibers that innervate both the abductor (posterior cricoarytenoid, PCA) muscle and adductor muscles of the vocal folds. Damage to the nerve compromises both of these functions and arrests the vocal folds in a near-closed position. In cases of bilateral vocal fold paralysis (BVFP), voice tends to be functional but airway embarrassment is often severe enough to warrant emergency tracheotomy to relieve inspiratory stridor and dyspnea.[1,2] If spontaneous recovery from nerve injury does not occur within one year, it is likely the patient will be chronically paralyzed. In such instances, long-term tracheostomy could be considered. Unfortunately, permanent tracheostomy is known to have the complications of tracheal stenosis, chronic infection, and psycho-social impairment.[3-5]
For this reason, laryngeal surgery is usually recommended to enlarge the airway and restore breathing through the mouth. Procedures such as arytenoidectomy and cordotomy, regarded as the standard of care for enlarging the airway, also have inherent complications [6-9]. Specifically, they destroy voice and compromise airway protection during swallowing.
As such, there is presently an unmet need for improved therapies for the treatment of laryngeal paralysis to facilitate return of normal ventilation.